CVE-2023-2783Network attack vector

Post modification via unchecked webhook secret

Published Jun 16, 2023 · Updated Dec 6, 2024

Missing authorization in Mattermost Apps Framework before 7.8.5, 7.9.4, and 7.10.1 allows remote authenticated users to alter App posts. The incoming-webhook handler accepts a caller-supplied secret without comparing it with the App's configured secret before applying supplied post content. A remote authenticated user can therefore submit forged webhook data that changes a post sent by an installed App, with no reported read or availability impact.

CVSS severity4.3
Medium
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in Mattermost Apps Framework before 7.8.5, 7.9.4, and 7.10.1 allows remote authenticated users to alter App posts. The incoming-webhook handler accepts a caller-supplied secret without comparing it with the App's configured secret before applying supplied post content. A remote authenticated user can therefore submit forged webhook data that changes a post sent by an installed App, with no reported read or availability impact.

The record

CVE
CVE-2023-2783
Published
Jun 16, 2023
Updated
Dec 6, 2024
Vendor
Mattermost
Product
Mattermost Apps Framework
Classifications
CWE-862, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 16, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=7.8.4
  2. Affected versionversion=0 <=7.9.3
  3. Affected versionversion=7.10.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermost Apps Frameworkversion=0 <=7.8.4; version=0 <=7.9.3; version=7.10.0

Published CVSS scores

4.3Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-862Missing Authorization
T1565.001Stored Data Manipulation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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